Diuretics

Question 1

Drug: Furosemide (Lasix®) (Loop Diuretic)

Answer 1

Uses: Pulmonary edema and the edema associated with heart failure, liver disease, nephrotic syndrome, ascites, hypertension.
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Most commonly used loop diuretic.

Question 2

Drug: Mannitol (Osmitrol®) (Osmotic Diuretic)

Answer 2

Most used osmotic diuretic.
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Administration: Intravenous (IV) infusion only.
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Storage: May crystallize when exposed to low temperatures; vials are often stored in a warmer.
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Administration Requirement: Use of a filter is required.

Question 3

Drug: Spironolactone (Aldactone®) (Potassium-Sparing Diuretic)

Answer 3

Also known as an aldosterone-inhibiting diuretic.
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Indications: Hyperaldosteronism, hypertension, reversing potassium loss caused by potassium-wasting diuretics, certain cases of heart failure: prevention of remodelling.
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Adverse Effects: Gynecomastia, amenorrhea, irregular menses, postmenopausal bleeding.

Question 4

Drug: Hydrochlorothiazide (Urozide®) (Thiazide Diuretic)

Answer 4

Example of a thiazide diuretic.
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Part of one of the most prescribed group of drugs for hypertension.

Question 5

Indication: Edema associated with heart failure and liver or kidney disease

Answer 5

Treated with loop diuretics.
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Carbonic anhydrase inhibitors are also used as adjunct therapy for edema secondary to heart failure.
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Thiazide and thiazide-like diuretics are indicated for edematous states

Question 6

Indication: Hypertension

Answer 6

Diuretic drugs are a mainstay of therapy for the treatment of hypertension.
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Loop diuretics can be used to control hypertension.
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Potassium-sparing diuretics (spironolactone and triamterene) are indicated for hypertension.
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Thiazide and thiazide-like diuretics are one of the most prescribed groups of drugs for hypertension.

Question 7

Indication: Glaucoma (Open-Angle and Secondary)

Answer 7

Carbonic anhydrase inhibitors are adjunct drugs in the long-term management of open-angle glaucoma and adjunct therapy for secondary glaucoma.
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Carbonic anhydrase inhibitors are used with miotics to lower intraocular pressure before ocular surgery in certain cases.

Question 8

Contraindication: Hypokalemia

Answer 8

Carbonic anhydrase inhibitors are contraindicated in patients with hypokalemia

Question 9

What percentage of sodium and water is typically reabsorbed in the proximal convoluted tubule?

Answer 9

60 to 70% of sodium and water is returned to the bloodstream by the proximal convoluted tubule

Question 10

What percentage of sodium is reabsorbed in the ascending loop of Henle?

Answer 10

20 to 25% of all sodium is reabsorbed into the bloodstream in the ascending loop of Henle.

Question 11

What percentage of sodium is reabsorbed in the distal convoluted tubule?

Answer 11

5 to 10% is reabsorbed in the distal convoluted tubule.

Question 12

What is the role of the collecting duct in filtrate processing?

Answer 12

The collecting duct is the final common pathway for the filtrate that started in the glomerulus.

Question 13

What are carbonic anhydrase inhibitors primarily used for in the long term?

Answer 13

Carbonic anhydrase inhibitors are primarily used as adjunct drugs in the long-term management of open-angle glaucoma and as adjunct therapy for secondary glaucoma.

Question 14

How are carbonic anhydrase inhibitors used before ocular surgery in certain glaucoma cases?

Answer 14

Carbonic anhydrase inhibitors are used with miotics to lower intraocular pressure before ocular surgery in certain cases.

Question 15

Besides glaucoma, what other conditions may carbonic anhydrase inhibitors be useful in treating?

Answer 15

Carbonic anhydrase inhibitors may also be useful in the treatment of: edema, secondary to heart failure; high-altitude sickness; and epilepsy.

Question 16

What are the main contraindications for using carbonic anhydrase inhibitors?

Answer 16

Contraindications for carbonic anhydrase inhibitors include: known drug allergy, hyponatremia, hypokalemia, severe kidney or liver dysfunction, adrenal gland insufficiency, and cirrhosis.

Question 17

List some common adverse effects associated with carbonic anhydrase inhibitors.

Answer 17

Common adverse effects associated with carbonic anhydrase inhibitors include: acidosis, hypokalemia, drowsiness, anorexia, paresthesias, hematuria, urticaria, photosensitivity, and melena (blood in the stool).

Question 18

How might carbonic anhydrase inhibitors interact with digoxin? Why?

Answer 18

Because carbonic anhydrase inhibitors can cause hypokalemia, an increase in digoxin toxicity may occur when they are combined with digoxin.

Question 19

What is a potential interaction between carbonic anhydrase inhibitors and corticosteroids?

Answer 19

Use of carbonic anhydrase inhibitors with corticosteroids may also cause hypokalemia.

Question 20

What are some drugs whose effects may be increased with concurrent use of carbonic anhydrase inhibitors?

Answer 20

The effects of amphetamines, carbamazepine, cyclosporine, phenytoin, and quinidine sulphate may be increased with concurrent use of carbonic anhydrase inhibitors.

Question 21

Name three common loop diuretic medications.

Answer 21

Three common loop diuretic medications are bumetanide, ethacrynic acid (rarely used clinically), and furosemide (Lasix®).

Question 22

What are the main indications for loop diuretics?

Answer 22

Main indications for loop diuretics include: edema associated with heart failure and liver or kidney disease; hypertension (to control); increasing kidney excretion of calcium in patients with hypercalcemia; and heart failure resulting from diastolic dysfunction.

Question 23

List some central nervous system adverse effects of loop diuretics.

Answer 23

Central nervous system adverse effects of loop diuretics include: dizziness, headache, tinnitus, and blurred vision.

Question 24

What are some gastrointestinal adverse effects of loop diuretics?

Answer 24

Gastrointestinal adverse effects of loop diuretics include: nausea, vomiting, and diarrhea.

Question 25

What are some hematological adverse effects of loop diuretics?

Answer 25

Hematological adverse effects of loop diuretics include: agranulocytosis, neutropenia, and thrombocytopenia.

Question 26

What are some metabolic adverse effects of loop diuretics?

Answer 26

Metabolic adverse effects of loop diuretics include: hypokalemia, hyperglycemia, and hyperuricemia.

Question 27

What are two potential types of toxicities associated with loop diuretics?

Answer 27

Loop diuretics can be neurotoxic and nephrotoxic

Question 28

What serum levels might loop diuretics increase?

Answer 28

Loop diuretics might increase serum levels of uric acid, glucose, alanine aminotransferase, and aspartate aminotransferase.

Question 29

How might the combination of a loop diuretic and metolazone (a thiazide) affect the nephron? What is this called?

Answer 29

Combining a loop diuretic with thiazide (metolazone) can result in sequential nephron blockade, leading to increased diuresis.

Question 30

How might NSAIDs affect the action of loop diuretics?

Answer 30

Nonsteroidal anti-inflammatory drugs (NSAIDs) may decrease the reduction of vascular resistance caused by loop diuretics.

Question 31

What is the most commonly used loop diuretic?

Answer 31

Furosemide (Lasix) is the most commonly used loop diuretic.

Question 32

What are some common uses for furosemide (Lasix)?

Answer 32

Furosemide (Lasix) is used for pulmonary edema and the edema associated with heart failure, liver disease, nephrotic syndrome, ascites, and hypertension.

Question 33

Name four examples of osmotic diuretics. Which is the most used?

Answer 33

Examples of osmotic diuretics include mannitol (Osmitrol®) (most used), urea, organic acids, and glucose.

Question 34

What are the main indications for osmotic diuretics?

Answer 34

Main indications for osmotic diuretics include: treatment of patients in the early, oliguric phase of acute kidney injury; to promote excretion of toxic substances; to reduce intracranial pressure; treatment of cerebral edema; and as a genitourinary irrigant.

Question 35

List some adverse effects associated with osmotic diuretics.

Answer 35

Adverse effects associated with osmotic diuretics include: convulsions, thrombophlebitis, pulmonary congestion, headaches, chest pains, tachycardia, blurred vision, chills, and fever.

Question 36

How is mannitol (Osmitrol) administered? What are some important considerations for its administration?

Answer 36

Mannitol (Osmitrol) is administered by intravenous (IV) infusion only. It may crystallize when exposed to low temperatures, so vials are often stored in a warmer, and use of a filter is required.

Question 37

What is another name for potassium-sparing diuretics? Name three examples.

Answer 37

Potassium-sparing diuretics are also known as aldosterone-inhibiting diuretics. Examples include amiloride (Midamor®), spironolactone (Aldactone®), and triamterene.

Question 38

For what conditions are spironolactone and triamterene typically indicated?

Answer 38

Spironolactone and triamterene are typically indicated for hyperaldosteronism, hypertension, reversing potassium loss caused by potassium-wasting diuretics, and certain cases of heart failure (prevention of remodelling).

Question 39

How does the long-term effectiveness of amiloride compare to spironolactone and triamterene?

Answer 39

Amiloride is similar to spironolactone and triamterene but less effective in the long term.

Question 40

What are some common central nervous system and gastrointestinal adverse effects of potassium-sparing diuretics?

Answer 40

Common central nervous system adverse effects include dizziness and headache. Gastrointestinal adverse effects include cramps, nausea, vomiting, and diarrhea.

Question 41

What is a key electrolyte imbalance to monitor for with potassium-sparing diuretics? What other general adverse effect might occur?

Answer 41

A key electrolyte imbalance to monitor for is hyperkalemia. Other general adverse effects include urinary frequency and weakness.

Question 42

List some specific adverse effects associated with spironolactone (Aldactone).

Answer 42

Specific adverse effects associated with spironolactone (Aldactone®) include gynecomastia, amenorrhea, irregular menses, and postmenopausal bleeding.

Question 43

What are some drug interactions to be aware of with potassium-sparing diuretics?

Answer 43

Drug interactions to be aware of include with lithium, angiotensin-converting enzyme inhibitors, potassium supplements, and NSAIDs.

Question 44

Name a common thiazide diuretic and three thiazide-like diuretics.

Answer 44

A common thiazide diuretic is hydrochlorothiazide (Urozide®). Thiazide-like diuretics include metolazone (Zaroxolyn®), chlorthalidone, and indapamide.

Question 45

What are the main indications for thiazide and thiazide-like diuretics?

Answer 45

ain indications for thiazide and thiazide-like diuretics include hypertension (one of the most prescribed groups), edematous states, idiopathic hypercalciuria, diabetes insipidus, and heart failure caused by diastolic dysfunction.

Question 46

What are some central nervous and gastrointestinal adverse effects of thiazide and thiazide-like diuretics?

Answer 46

Central nervous adverse effects include dizziness, headache, and blurred vision. Gastrointestinal adverse effects include anorexia, nausea, vomiting, and diarrhea.

Question 47

What are some genitourinary, hematological, and integumentary adverse effects of thiazide and thiazide-like diuretics?

Answer 47

Genitourinary: erectile dysfunction. Hematological: jaundice, leukopenia, agranulocytosis. Integumentary: urticaria, photosensitivity.

Question 48

What are some metabolic adverse effects of thiazide and thiazide-like diuretics?

Answer 48

Metabolic adverse effects include hypokalemia, glycosuria, hyperglycemia, hyperuricemia, and hypochloremic alkalosis.

Question 49

What are some key aspects of nursing assessment that should be performed before initiating diuretic therapy?

Answer 49

Key aspects include: thorough patient history and physical examination; assessment of baseline fluid volume status, intake and output, serum electrolyte values, weight, and vital signs (especially postural blood pressure); and assessment for contraindications or need for cautious use.

Question 50

When should patients ideally take their diuretic medication, and why?

Answer 50

Patients should ideally take their medication in the morning if possible to avoid interference with sleep patterns due to increased urination.

Question 51

What electrolyte level is crucial to monitor during diuretic therapy?

Answer 51

It is crucial to monitor serum potassium levels during therapy.

Question 52

What dietary education should nurses provide to patients taking most diuretics (excluding potassium-sparing)?

Answer 52

Nurses should teach patients to maintain proper nutritional and fluid volume status and to eat more potassium-rich foods.

Question 53

What instructions should nurses provide to patients regarding changes in position to minimize adverse effects of diuretics?

Answer 53

Teach patients to change positions slowly and to rise slowly after sitting or lying, to prevent dizziness and fainting related to orthostatic hypotension.

Question 54

What self-monitoring activity should nurses encourage patients taking diuretics to perform daily?

Answer 54

Encourage patients to keep a log of their daily weight.

Question 55

List some signs and symptoms of hypokalemia that patients should be aware of.

Answer 55

Signs and symptoms of hypokalemia include anorexia, nausea, lethargy, muscle weakness, mental confusion, and hypotension.